Biology subjects

Male, V.

Publications and source records attributed to Male, V..

6 recordsLinked to original sources

bioRxiv2024

Dynamic roles of ILC3 in endometrial repair and regeneration

Innate lymphoid cells (ILC) are prominent in the human uterine mucosa and play physiological roles in pregnancy. ILC3 are the second-most common ILC subset in the uterine mucosa, but their role remains unclear. Here we define two subsets of lineage-negative CD56+ CD117+ CRTH2-uterine ILC3, distinguished by their expression of CD127. The CD127-subset is most numerous and active during menstruation and immediately after parturition, suggesting a role in repair of the uterine mucosa (called endometrium outside of pregnancy); the CD127+ subset is most numerous and active immediately after menstruation, as the endometrium regenerates. In healthy endometrium, ILC3 are spatially associated with glandular epithelial and endothelial cells, which both express receptors for the ILC3-derived cytokines, IL-22 and IL-8. In the eutopic endometrium of people with endometriosis, ILC3 are located further from glandular epithelial and endothelial cells suggesting that these cells may be less exposed to ILC3 products, potentially with negative consequences for endometrial regeneration. Our findings highlight the dynamic nature of ILC3 in the uterine mucosa and suggest their primary role is in repair and regeneration. An improved understanding of uterine ILC3 will inform future research on endometrial health and disease.

immunology↗

bioRxiv2023

An integrated single-cell reference atlas of the human endometrium

The human endometrium, the inner lining of the uterus, exhibits complex, dynamic changes throughout the menstrual cycle in response to ovarian hormones. Aberrant response of endometrial cells to hormones is associated with multiple disorders, including endometriosis. Previous single-cell studies of the endometrium profiled a limited number of donors and lacked consensus in defining cell types and states. Here, we introduce the Human Endometrial Cell Atlas (HECA), a high-resolution single-cell reference atlas, combining published and newly generated single-cell transcriptomics datasets of endometrial biopsies of women with and without endometriosis. The HECA assigned consensus cell types and states, and uncovered novel ones, which we mapped in situ using spatial transcriptomics. We quantified how coordinated interactions between cell states in space and time contribute to endometrial regeneration and differentiation. In the continuously changing functionalis layer, we identified an intricate coordination of TGF{beta} signalling between stromal and epithelial cells, likely crucial for cell differentiation. In the basalis layer, we defined signalling between fibroblasts and a new epithelial cell population expressing epithelial stem/progenitor markers, suggesting their role in endometrial regeneration. Additionally, integrating the HECA single-cell data with genome-wide association study data and comparing endometrial samples from women with and without endometriosis, we pinpointed subsets of decidualised stromal cells and macrophages as the most dysregulated cell states in endometriosis. Overall, the HECA is an invaluable resource for studying endometrial physiology, investigating endometrial disorders, and guiding the creation of endometrial microphysiological in vitro systems.

genomics↗

bioRxiv2022

Uterine NK cells underexpress receptors recognizing HLA-C2 and HLA-G in reproductive failure

A significant proportion of recurrent miscarriage, recurrent implantation failure and infertility are unexplained, and these conditions have been proposed to have an etiology of immunological dysfunction at the maternal-fetal interface. Uterine Natural Killer cells (uNK) comprise three subsets and are the most numerous immune cells found in the uterine mucosa at the time of implantation. They are thought to play an important role in successful pregnancy by regulation of extravillous trophoblast (EVT) invasion and spiral artery remodelling. Here, we examine the frequency, phenotype and function of uNK1-3 from the uterine mucosa of 16 women with unexplained reproductive failure compared to 11 controls with no reproductive problems, during the window of implantation. We report that KIR2DL1/S1 and LILRB1 expression is lower in the reproductive failure group for both uNK (total uNK, uNK 2 and 3) and pNK. We also show that degranulation activity is significantly reduced in total uNK, and that TNF- production is lower in all uNK subsets in the reproductive failure group. Taken together, our findings suggest that reproductive failure may be caused by global reduction in expression of uNK receptors important for interaction with HLA-C and HLA-G on EVT during early pregnancy, leading to reduced uNK activation. This is the first study to examine uNK subsets during the window of implantation in women with reproductive failure and will serve as a platform to focus on particular aspects of phenotype and function of uNK subsets in future studies. Further understanding of uNK dysregulation is important to establish potential diagnostic and therapeutic targets in the population of women with unexplained reproductive failure.

immunology↗

bioRxiv2022

Dynamic changes in uterine NK cell subset frequency and function over the menstrual cycle and pregnancy

Uterine Natural Killer cells (uNK) play an important role in promoting successful pregnancy by regulating trophoblast invasion and spiral artery remodelling in the first trimester. Recently, single cell RNA sequencing (scRNAseq) on first trimester decidua showed that uNKs can be divided into three subsets, which may have different roles in pregnancy. Here we present an integration of previously published scRNAseq datasets, together with novel flow cytometry data to interrogate the frequency, phenotype and function of uNK1-3 in seven stages of the reproductive cycle (menstrual, proliferative, secretory phases; first, second, third trimester; and postpartum). We found that uNK1 and -2 peak in the first trimester, but by the third trimester the majority of uNK are uNK3. All three subsets are most able to degranulate and produce cytokines during the secretory phase of the menstrual cycle and express KIR2D molecules, which allow them to interact with HLA-C expressed by placental extravillous trophoblast cells, at the highest frequency during the first trimester. Taken together, our findings suggest that uNK are particularly active and able to interact with placental cells at the time of implantation, and that uNK1 and 2 may be particularly involved in these processes. Our findings are the first to establish how uNK frequency and function changes dynamically across the healthy reproductive cycle. This serves as a platform from which the relationship between uNK function and impaired implantation and placentation can be investigated. This will have important implications for the study of subfertility, recurrent miscarriage, pre-eclampsia and pre-term labour.

immunology↗

bioRxiv2019

Tbet promotes NK cell bone marrow egress via CXCR6 expression

Tbet-deficient mice have reduced NK cells in blood and spleen, but increased NK cells in bone marrow and lymph nodes, a phenotype that is thought to be due to defective migration. Here, we revisit the role of Tbet in NK cell bone marrow egress. We definitively show that the accumulation of NK cells in the bone marrow of Tbet-deficient (Tbx21-/-) animals occurs because of a cell-intrinsic migration defect. We identify a profile of gene expression, co-ordinated by Tbet, which affects the localisation of NK cells in the bone marrow. Tbet promotes Cxcr6 expression and immature NK cells accumulate in the bone marrow of CXCR6-deficient mice. This suggests that CXCR6 is among the mediators of migration, controlled by Tbet, that co-ordinate NK cell bone marrow egress.

immunology↗

bioRxiv2019

The obese liver environment mediates conversion of NK cells to a less cytotoxic ILC1-like phenotype

The liver contains both NK cells and their less cytotoxic relatives, ILC1. Here, we investigate the role of NK cells and ILC1 in the obesity-associated condition, non-alcoholic fatty liver disease (NAFLD). In the livers of mice suffering from NAFLD, NK cells are less able to degranulate, express lower levels of perforin and are less able to kill cancerous target cells than those from healthy animals. This is associated with a decreased ability to kill cancer cells in vivo. On the other hand, we find that perforin-deficient mice suffer from less severe NAFLD, suggesting that this reduction in NK cell cytotoxicity may be protective in the obese liver, albeit at the cost of increased susceptibility to cancer. The decrease in cytotoxicity is associated with a shift towards a transcriptional profile characteristic of ILC1, increased expression of the ILC1-associated proteins CD200R1 and CD49a, and an altered metabolic profile mimicking that of ILC1. We show that the conversion of NK cells to this less cytotoxic phenotype is at least partially mediated by TGF{beta}, which is expressed at high levels in the obese liver. Finally, we show that reduced cytotoxicity is also a feature of NK cells in the livers of human NAFLD patients.

immunology↗